Booked my first blood donation for today, drank plenty, got there and when it came to the vein check the only vein they could find is only good enough for blood samples apparently. Was told it was common among young women (I’m 28) and veins can change so try again in 2 years if it is something I’d still like to do. I’ve had blood samples taken regularly over the last 2.5 years and phlebotomists always have a little moan about me not having great veins so I know in over 2 years my veins haven’t changed so is there anything I can actually do to improve my chances of donating?